1. Field of the Invention
The present invention relates to a motor mounted to a disk drive apparatus and, more particularly, to a motor including a circuit board with electronic parts attached thereto.
2. Description of the Related Art
In recent years, the reduction in the overall thickness of portable devices leads to an increasing demand for a low-profile disk drive apparatus mounted to the portable devices. In order to provide the low-profile disk drive apparatus, it is necessary to reduce the overall thickness of a traverse unit. The traverse unit includes an optical pickup mechanism arranged to emit and receive light to and from a disk, a motor arranged to rotate the disk and a chassis arranged to support the optical pickup mechanism and the motor. The motor is fixed to the chassis by using, e.g., screws. One example of this configuration is disclosed in Japanese Patent Laid-open Publication No. 2007-280509.
In case the motor is fixed to the chassis with screws, the heads of screws protrude beyond the lower surface of an attachment plate. This makes it difficult to reduce the overall thickness of the traverse unit.
In view of this, there has been proposed a method in which a space for accommodating screw heads is defined by forming the screw attachment portions of an attachment plate of a motor higher than the remaining portion of the attachment plate. One example of the configuration using this method is disclosed in Japanese Patent Laid-open Publication No. 2005-253239.
A circuit board is attached to the upper surface of the attachment plate of the motor. The end portions of coils of a stator included in the motor are connected to the circuit board. In case electronic parts are bonded to the circuit board by soldering, the task of attaching the circuit board to the attachment plate precedes the task of bonding the electronic parts to the circuit board. This is to secure positional accuracy of the electronic parts. When bonding the electronic parts to the circuit board, soldering is preliminarily performed on the portions to which the electronic parts are to be bonded.
As mentioned above, the screw attachment portions of the attachment plate of the motor are formed higher than the remaining portion of the attachment plate with a view to reduce the overall thickness of the traverse unit. For that reason, the upper surfaces of the screw attachment portions are positioned higher than the upper surface of the circuit board. As a result, it is impossible for a mounting unit to carry out the task of preliminarily performing soldering on the circuit board. Therefore, the task of preliminarily performing soldering on the circuit board needs to be manually carried out by a worker. This sharply reduces the motor production efficiency.